Update sendDMOperation to send notifs as well

Summary: This differential updates sendDMOperation to create and send notifs as well

Test Plan:

1. Apply this patch: https://gist.github.com/marcinwasowicz/2db9332e8d59225d5549fe2e4e29d4cf
2. Send message from web to native client.
3. Ensure that client displays a list of different notifications including:
   1. text message notif
   2. thread creation notif
   3. reaction notif
   4. thread settings change notifs
   5. sidebar creation notif

Reviewers: tomek, kamil

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13123